Posts of Ivan H Plauchu RSSFri, 08 Jan 2021 11:42:17 GMThttps://www.ncbi.nlm.nih.gov/pmc/articles/PMC4732815/

]]>Fri, 08 Jan 2021 11:42:17 GMTTibetan Mastiff Found to Gain High-Altitude Adaptation after Domestication by Interbreeding with the Tibet Gray Wolf  The Tibetan mastiff is famed for its high-altitude prowess, showing a remarkable strength and endurance to 3-mile elevations and even higher. Evolutionary biologists have successfully identified the genes responsible for this adaptation, yet an elusive question remained: Exactly how did they acquire the adaptation? The answer, found by a Chinese research group led by Zhen Wang and Yixue Li, sheds light on not only the genetic origins of high-altitude elevation, but also a remarkable tale of interbreeding in the adaptation of both dog and modern man . Their new study demonstrates strong genetic evidence that, when man first settled into the Tibetan plateau, the recently domesticated Tibetan Mastiff interbred with the Tibet gray wolf, and a DNA swap being introduced at two genomic hotspots is the key to acquiring their special high altitude powers. The recent sequencing of the dog and wolf genomes has been a boon of study to evolutionary biologists. Now, the Chinese group utilized the genomes for their comparative Tibetan study. First, they showed that Tibetan Mastiffs are much more closely related with other Chinese dogs rather than gray wolves. Second, they found two unique genomic hotspots, the EPAS1 and HBB loci, that show the significant signals of interbreeding with the Tibet gray wolf and underwent strong positive selection. And in a spectacular coincidence, it turns out to be the same location, same gene, same mechanism —interbreeding—as in humans. And as for modern humans? Well, other recent studies (http://www.nature.com/nature/journal/v512/n7513/full/nature13408.html) suggest that Tibetans repeated this interbreeding adaptation—recent evidence shows that they may have also acquired their high-altitude adaptation by interbreeding with an ancient hominid known as the Denisovans. Even in evolutionary biology, history may have a way of r... Read more

]]>Fri, 08 Jan 2021 07:59:08 GMTGenetic analysis of the dog genotype.

]]>Fri, 08 Jan 2021 04:21:35 GMTResumen En este estudio se determinó la secuencia completa del genoma mitocondrial del Mastín Tibetano (ADNmt) y  se analizaron las relaciones filogenéticas entre el Mastín Tibetano y otras especies de  Cánidos utilizando el coyote ( Canis latrans ) como exogrupo. La secuencia completa de nucleótidos del mtDNA del mastín tibetano era de 16710 pb e incluía 22 genes de tRNA, gen de rRNA 2S, 13 genes que codifican proteínas y una región no codificante (región del bucle D), que es similar a otros genomas mitocondriales de mamíferos. . Se  analizaron en detalle las características de los genes que codifican proteínas, la región no codificante, los genes de tRNA y rRNA entre  Canidae .Árboles de cánidos de máxima parsimonia y unión de  vecinos  construido utilizando 12 genes codificadores de proteínas mitocondriales mostró que a medida que los coyotes y los lobos tibetanos se agrupaban, también lo hacían los lobos grises y los perros domésticos, lo que sugiere que el mastín tibetano se originó a partir del lobo gris al igual que otros perros domésticos. Los perros domésticos se agruparon en cuatro clados, lo que implica al menos cuatro orígenes maternos (A a D). Clustering analysis and networking revealed the presence of a closer relative between the Tibetan Mastiff and the Old English sheepdog, Newfoundland, Rottweiler and Saint Bernard, which confirms that many well-known large breed dogs in the world, such as the Old English sheepdog, may have the same blood lineage as that of the Tibetan Mastiff. ... Read more

]]>Thu, 07 Jan 2021 22:03:08 GMTCalabrian Cane Corso working bloodlines (Linea di sangue calabrese Solo sangue amaro)

]]>Thu, 07 Jan 2021 03:26:49 GMTVintage... #Boxer 1905 Gracie's Miss Edith, Dog Show 1915 #Pug 1890 Henry Bernard Chalon (1770 - 1845) "Pugs" Cerchia di Paul de Vos (1595-1678) "Chiens attaqués par un sanglier" George Morland (1763/1804) "Dogs Fighting"

]]>Thu, 07 Jan 2021 03:24:46 GMT"Caza del jabalí" 1611 Roelandt Savery (1576/1639)

]]>Thu, 07 Jan 2021 03:18:08 GMTHound by Anthony van Dyck (1599–1641)

]]>Wed, 30 Dec 2020 05:17:19 GMTDalbohund in Sweden,  Gotala (Sweden) between 1900 and 1910

]]>Mon, 28 Dec 2020 05:51:21 GMTGrece, Vth Century BC

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